Apple is trying to build a massive moat around their iOS/OSX ecosystem. If they can execute, it will be difficult for competitors to convert iOS users to other platforms.

  -Applications synced across multiple devices
  -music, photos, calendars, apps in iCloud (including your ripped content)
  -Integration with iTouch/iPad/iPhone docks and accessories
  -iMessage/Facetime lock in for user accounts
  -Gamecenter achievements
  -OSX integration and "feel" 
  -Reduce the need for a PC with wireless updates and sync (probably 75% of iOS users are on Windows)

The average user will have to face the prospect of changing out a lot of their software as they become more integrated into Apple's ecosystem.